Usually, when the police examines whether or not a driver is drunk by using a blood alcohol testing device called a breathalyzer that is the brand name of a breath alcohol testing instrument manufacturer, the driver is made to breathe on an inlet of the blood alcohol testing device, to then enable the blood alcohol testing device to measure alcohol concentration from a breath sample and externally display a result of the measured alcohol concentration. This breath sample type alcohol testing instrument is widely used. The drivers who object to accuracy of the blood alcohol testing device are tested on whether or not they are drunk through blood collection.
However, in the case that a driver becomes unconscious due to occurrence of a car accident, it may not use the breath sample type blood alcohol testing device. In this case, it cannot but inevitably employ a blood sample type alcohol testing instrument that estimates blood alcohol content from a blood sample through blood-gathering. It may consume a considerable amount of time and cost as well as cause cumbersome legal procedures to gather blood of an unconscious person without consent. In addition, since a blood sampling approach through the blood-gathering takes a long time, it may be difficult to accurately measure blood alcohol content (BAC) at the time of the car accident. In other words, since the alcohol absorbed into the body is decomposed at a rate of 0.015%/h, it may be difficult to trust the measured blood alcohol concentration level after a long period of time has elapsed. Therefore, there is the need to quickly and accurately measure blood alcohol content (BAC) from an unconscious person at the time of the car accident.